U.S. patent number 7,951,214 [Application Number 10/567,463] was granted by the patent office on 2011-05-31 for filter cleaning system for a vacuum cleaner.
This patent grant is currently assigned to AB Electrolux. Invention is credited to Mathias Belin, Anna-Karin Gray, Henrik Holm, Mattias Jansson, Finn Lofnes, Lars Mennborg, Linda Menrik, Hakan Miefalk, Anna-Karin Trydegard.
United States Patent |
7,951,214 |
Menrik , et al. |
May 31, 2011 |
Filter cleaning system for a vacuum cleaner
Abstract
This invention relates to a vacuum cleaner comprising a body
with a vacuum source. The vacuum cleaner is provided with at least
two filter chambers, a first filter chamber for a first filter
means in a surface cleaning mode and a second chamber for the same
or a second filter means in a filter cleaning mode.
Inventors: |
Menrik; Linda (Hagersten,
SE), Gray; Anna-Karin (Stockholm, SE),
Lofnes; Finn (Coye la For t, FR), Miefalk; Hakan
(Jarfalla, SE), Jansson; Mattias (Pordenone,
IT), Trydegard; Anna-Karin (Stockholm, SE),
Belin; Mathias (Saltsjo-Boo, SE), Holm; Henrik
(Stockholm, SE), Mennborg; Lars (Vikingstad,
SE) |
Assignee: |
AB Electrolux (Stockholm,
SE)
|
Family
ID: |
32396415 |
Appl.
No.: |
10/567,463 |
Filed: |
November 26, 2004 |
PCT
Filed: |
November 26, 2004 |
PCT No.: |
PCT/SE2004/001756 |
371(c)(1),(2),(4) Date: |
December 05, 2006 |
PCT
Pub. No.: |
WO2005/053497 |
PCT
Pub. Date: |
June 16, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20070125049 A1 |
Jun 7, 2007 |
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Foreign Application Priority Data
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Dec 4, 2003 [SE] |
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0303277 |
May 6, 2004 [SE] |
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0401183 |
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Current U.S.
Class: |
55/288; 55/DIG.3;
95/271; 55/484; 55/302; 95/269; 55/301; 95/268; 95/280;
15/415.1 |
Current CPC
Class: |
A47L
9/20 (20130101); A47L 9/1666 (20130101); Y10S
55/03 (20130101) |
Current International
Class: |
B01D
39/00 (20060101) |
Field of
Search: |
;55/324,337,DIG.3,434-465,288,301,302,484 ;96/380-388
;95/268-269,271,280 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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41 38 223 |
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Feb 1993 |
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DE |
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4-352925 |
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Dec 1992 |
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JP |
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2002-28107 |
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Jan 2002 |
|
JP |
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WO 85/02528 |
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Jun 1985 |
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WO |
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WO 90/12532 |
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Nov 1990 |
|
WO |
|
Primary Examiner: Greene; Jason M
Assistant Examiner: Hawkins; Karla
Attorney, Agent or Firm: Hunton & Williams
Claims
The invention claimed is:
1. A vacuum cleaner comprising: a nozzle configured to be traversed
on a surface to be cleaned, the nozzle having an internal passage
defined by a nozzle inlet positioned to be substantially adjacent
the surface to be cleaned and a nozzle outlet remote from the
nozzle inlet; a vacuum source configured to generate a working air
flow, the working air flow passing through the vacuum cleaner along
an air flow path; a separation system configured to separate
particles from the working air flow, the separation system
comprising a first filter chamber; a filter cleaning system
comprising a second filter chamber having a second filter chamber
inlet and a second filter chamber outlet, the second filter chamber
outlet being shaped as an elongated slot; a first dirt filter
configured to be alternatively placed in the first filter chamber
and the second filter chamber; and wherein: the elongated slot is
positioned adjacent a relatively small portion of a total surface
area of the filter and extends along substantially an entire length
of the first dirt filter, the first dirt filter is configured to be
movable relative to the slot when the first dirt filter is placed
in the second filter chamber to thereby incrementally expose
substantially the total surface area of the filter to the slot, and
the air flow path comprises switching means for switching between a
surface cleaning mode in which the working air flow enters the
nozzle inlet and passes through the first filter chamber to entrap
dirt particles in the first dirt filter when the first dirt filter
is located in the first filter chamber, and a filter cleaning mode
in which the working air flow passes through the second filter
chamber to displace dirt particles from the first dirt filter when
the first dirt filter is located in the second filter chamber.
2. The vacuum cleaner of claim 1, wherein the working air flow does
not pass through the second filter chamber when the air flow path
is in the surface cleaning mode.
3. The vacuum cleaner of claim 1, wherein the working air flow does
not pass through the first filter chamber when the air flow path is
in the filter cleaning mode.
4. The vacuum cleaner of claim 1, wherein the working air flow
passes through the first dirt filter in a first direction when the
air flow path is in the surface cleaning mode, and the working air
flow passes through the first dirt filter in a second direction
when the air flow path is in the filter cleaning mode, the second
direction being generally opposite the first direction.
5. The vacuum cleaner of claim 1, wherein the separation system
further comprises a cyclone separator configured to remove dirt
from the working airflow, and wherein the air flow path passes
through the cyclone chamber to remove dirt from the working air
flow when the air flow path is in the surface cleaning mode.
6. The vacuum cleaner of claim 5, wherein the cyclone separator is
located upstream of the first filter chamber when the air flow path
is in the surface cleaning mode.
7. The vacuum cleaner of claim 1, wherein the separation system
further comprises a cyclone separator configured to remove dirt
from the working airflow, and wherein the air flow path passes
through the cyclone chamber to remove dirt from the working air
flow when the air flow path is in the filter cleaning mode.
8. The vacuum cleaner of claim 7, wherein the cyclone separator is
located downstream of the second filter chamber when the air flow
path is in the filter cleaning mode.
9. The vacuum cleaner of claim 1, further comprising an ambient air
inlet, wherein the second filter chamber is located downstream of
the ambient air inlet when the air flow path is in the filter
cleaning mode.
10. The vacuum cleaner of claim 1, further comprising a valve
configured to switch the vacuum cleaner between the surface
cleaning mode and the filter cleaning mode.
11. The vacuum cleaner of claim 1, further comprising a second dirt
filter, the second dirt filter being configured to be alternatively
placed in the first filter chamber when the first dirt filter is in
the second filter chamber, and in the second filter chamber when
the first dirt filter is in the first filter chamber.
12. The vacuum cleaner of claim 11, further comprising a support
structure having a first end attached to the first dirt filter, and
a second end attached to the second dirt filter, the support
structure further being removable from the vacuum cleaner with the
first dirt filter and second dirt filter attached thereto.
13. The vacuum cleaner of claim 12, wherein the first filter
chamber is adjacent the second filter chamber, and the support
structure overbridges a distance between the first filter chamber
and the second filter chamber, and the support structure can be
manipulated to position the first dirt filter in the first filter
chamber and the second dirt filter in the second filter chamber, or
to position the first dirt filter in the second filter chamber and
the second dirt filter in the first filter chamber.
14. The vacuum cleaner of claim 1, wherein the first dirt filter is
movable when placed in the second filter chamber, and movement of
the first dirt filter activates the vacuum source to cause the
working air flow to move through the vacuum cleaner when the air
flow path is in the filter cleaning mode.
15. The vacuum cleaner of claim 14, wherein the filter comprises a
filter cartridge having a cylindrical profile, the filter cartridge
being rotatable about a longitudinal axis thereof.
16. The vacuum cleaner of claim 1, wherein: the first dirt filter
comprises a filter cartridge having a cylindrical profile; and the
slot is positioned proximal to an outer periphery of the filter
cartridge and extends substantially parallel to a longitudinal axis
of the filter cartridge.
17. A vacuum cleaner comprising: a vacuum source configured to
generate a working air flow; an inlet nozzle configured to be
traversed on a surface to be cleaned; a dirt separation system
comprising a first filter chamber having a first filter chamber
inlet and a first filter chamber outlet; a filter cleaning system
comprising a second filter chamber having a second filter chamber
inlet and a second filter chamber outlet; a clean air outlet; a
filter configured to be selectively and alternatively positioned in
the first filter chamber and the second filter chamber, and having
a surface configured to hold dirt particles; and an air flow system
comprising: a surface cleaning air flow path extending from the
inlet nozzle to the first filter chamber inlet, from the first
filter chamber inlet through the filter surface in a first
direction when the filter is positioned in the first filter chamber
and to the first filter chamber outlet, through the vacuum source,
and then to the clean air outlet; and a filter cleaning air flow
path extending from an ambient air inlet to the second filter
chamber inlet, from the second filter chamber inlet through the
filter surface in a second direction when the filter is positioned
in the second filter chamber and to the second filter chamber
outlet, the second direction being generally opposite the first
direction, through the vacuum source, and then to the clean air
outlet; wherein the second filter chamber outlet comprises an
elongated slot positioned adjacent a relatively small portion of a
total surface area of the filter and extending along substantially
the entire length of the filter when the filter is positioned in
the second filter chamber, and the filter is movable within the
second filter chamber to incrementally expose the total surface
area of the filter to elongated slot.
18. The vacuum cleaner of claim 17, in which the air flow system
further comprising a valve configured to selectively choose one or
the other of the surface cleaning air flow path and the filter
cleaning air flow path.
19. The vacuum cleaner of claim 17, wherein the dirt separation
system comprises a cyclone separator fluidly connected between the
inlet nozzle and the first filter chamber in the surface cleaning
air flow path, and fluidly connected between the second filter
chamber and the clean air outlet in the filter cleaning air flow
path.
20. The vacuum cleaner of claim 17, further comprising a second
filter configured to be positioned in the first filter chamber when
the filter is in the second filter chamber, and in the second
filter chamber when the filter is in the first filter chamber.
21. A vacuum cleaner comprising: an inlet configured to receive a
first flow of air; a particle separator configured to separate
particles from the first flow of air; a first filter chamber
positioned downstream from the particle separator and configured to
receive the first flow of air; a filter cleaning chamber configured
to receive a second flow of air; a vacuum source configured to
generate the first flow of air and the second flow of air; and a
removable first filter configured to be positioned in the first
filter chamber during normal operation to receive the first flow of
air in a first direction therethrough, and further configured to be
removed from the first filter chamber and inserted into the filter
cleaning chamber to receive the second flow of air in a second
direction therethrough to thereby clean the first filter; wherein
the filter cleaning chamber comprises an air outlet in fluid
communication with the vacuum source, the air outlet being
positioned adjacent a relatively small portion of a total surface
area of the filter and comprising an elongated slot that extends
along substantially an entire length of the first filter; and
wherein the first filter is mounted within the filter cleaning
chamber by a movable mount that permits the first filter to be
moved generally transverse to the elongated slot to thereby
incrementally position the total surface area of the filter
adjacent the elongated slot.
22. The vacuum cleaner of claim 21, further comprising a removable
second filter, wherein the first filter and the second filter can
be interchanged between the first filter chamber and the filter
cleaning chamber for alternatively cleaning the first filter and
the second filter.
23. A vacuum cleaner comprising: a filter having a dirt-receiving
side configured to block the flow of particles therethrough; a
first filter chamber comprising a first filter chamber inlet, a
first filter chamber outlet, and a first filter chamber filter
receptacle configured to selectively hold the filter fluidly
between the first filter chamber inlet and the first filter chamber
outlet, with the dirt-receiving side facing the first filter
chamber inlet; a second filter chamber comprising a second filter
chamber inlet, a second filter chamber outlet, and a second filter
chamber filter receptacle configured to selectively hold the filter
fluidly between the second filter chamber inlet and the second
filter chamber outlet, with the dirt-receiving side facing the
second filter chamber outlet; a vacuum source configured to
generate a first flow of air from the first filter chamber inlet to
the first filter chamber outlet, and a second flow of air from the
second filter chamber inlet to the second filter chamber outlet;
wherein the second filter chamber outlet is positioned adjacent a
relatively small portion of a total surface area of the filter and
comprises an elongated slot positioned adjacent the filter and
extending along substantially an entire length of the filter, and
the filter is movable within the second filter chamber to
incrementally expose the total surface area of the filter to
elongated slot.
24. The vacuum cleaner of claim 23, further comprising a cyclone
separator, the cyclone separator being selectively and
alternatively fluidly connectable to the first filter chamber inlet
and the second filter chamber outlet.
Description
FIELD OF THE INVENTION
The present invention relates to a vacuum cleaner. More
particularly, embodiments of the invention relate to apparatus and
methods for cleaning filters used in a vacuum cleaner.
BACKGROUND OF THE INVENTION
Traditional vacuum cleaners usually belong to two different
categories called canister cleaners and upright cleaners. The
canister vacuum cleaner comprises a housing enclosing an electric
fan unit that creates an airflow from a vacuum cleaner nozzle
through a tube shaft and a hose and further through a separating
system comprising a porous bag collecting the dust before the air
reaches the fan and leaves the housing to the ambient air. The
upright vacuum cleaner differs from the canister cleaner in that
the tube shaft and the hose are eliminated and that the nozzle,
that often is provided with a rotating brush, is pivotally
connected to the vacuum cleaner housing. The housing encloses the
fan unit and the air pervious dust bag and is provided with a
handle to move the complete vacuum cleaner on the floor.
In order to further clean the air before the air leaves the vacuum
cleaners mentioned above additional filters are arranged after the
dust bag as seen in the air flow direction. These filters are
usually placed such that they can easily be removed and be replaced
by a new filter. As an alternative certain filters might be taken
away in order to be cleaned by manual operations or by washing or
rinsing the filter in water and/or cleaning agents.
There are also so called cyclone vacuum cleaners on the market, see
for instance EP 00850060.1, that are provided with a different type
of dust separation system. Instead of using an air pervious
collecting bag the dust is separated by means of a vortex created
in a circular cyclone chamber. The particles are by means of
centrifugal action directed outwards from the centre of the vortex
and are collected in a collecting container whereas the cleaned air
is taken out from the center of the vortex. The clean air is then
sucked to the vacuum source and flows out from the vacuum cleaner
to the ambient air. Even if the main part of the dust particles
that are present in the dust laden air are separated by the cyclone
a minor part of the particles follow the clean airflow out of the
cyclone. Consequently also for this type of vacuum cleaners there
is a need for filters in the air passages after the cyclone chamber
in order to get an efficient cleaning of the air flowing out from
the vacuum cleaner.
It is a disadvantage that the operator of all of the vacuum
cleaners mentioned above has to remove the filter and replace it or
clean it since replacement means that the consumer always has to
keep an eye on the consumption of the filter and to buy new filters
when necessary whereas cleaning means that the vacuum cleaner can
not be used during the washing period and moreover demands for
certain cumbersome activities from the operators side.
It has also been proposed, see WO 85/02528, to provide a vacuum
cleaner with two electrical motors (FIGS. 1-4) each having a filter
that is placed in a common dust collecting chamber. In order to
clean the filters the airflow through each filter is reversed by
means of the other motor. The same publication also shows a vacuum
cleaner arrangement (FIGS. 5-6) that is provided with one motor and
one main filter and an auxiliary filter the filters also being
placed in a common dust collecting chamber. In order to clean the
main filter the airflow is reversed and directed through the
auxiliary filter. A clear disadvantage with the first arrangement
is the need for two motors whereas there is no indication how to
clean the auxiliary filter in the second arrangement.
SUMMARY OF THE INVENTION
A first purpose of this invention is to create an arrangement that
eliminates the above drawbacks making it possible for the operator
to change a filter quickly and to easily keep track of the filter
condition. Another purpose of the invention is to create an
arrangement that makes it possible to easily clean the filter
without taking the vacuum cleaner out of operation or using
cumbersome methods for cleaning the filter.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute
a part of this specification, illustrate embodiments of the
invention and, together with the description, serve to explain the
principles of the invention.
In the drawings,
FIG. 1 shows a schematic view of vacuum cleaner comprising a first
embodiment of the invention. The schematic shows a first filter in
an active position and a second filter is in an inactive
position.
FIG. 2 shows a schematic view of vacuum cleaner comprising a first
embodiment of the invention. The schematic shows a first filter in
an inactive position and a second filter is in an active
position.
FIG. 3 shows a schematic view of vacuum cleaner comprising a first
embodiment of the invention. The schematic shows the airflow
through the vacuum cleaner when a first filter is cleaned.
FIG. 4 shows a schematic view of vacuum cleaner comprising a first
embodiment of the invention. The schematic shows the airflow
through the vacuum cleaner when a second filter is cleaned.
FIG. 5 shows a schematic view of vacuum cleaner comprising a second
embodiment of the invention. The schematic shows a first filter in
an active position during an ordinary vacuum cleaning operation and
a second filter is in an inactive, stored position.
FIG. 6 shows a schematic view of vacuum cleaner comprising a second
embodiment of the invention. The schematic shows a filter being
cleaned in the stored position.
FIG. 7 shows an alternative schematic view of vacuum cleaner
comprising an embodiment of the invention.
FIG. 8 shows an exploded view of a body of a vacuum cleaner
comprising an embodiment of the invention.
FIG. 9 is a schematic drawing of an embodiment of a filter rotating
mechanism.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description is intended to convey a thorough
understanding of the invention by providing a number of specific
embodiments and details involving a vacuum cleaner. It is
understood, however, that the invention is not limited to these
specific embodiments and details, which are exemplary only. It is
further understood that one possessing ordinary skill in the art,
in light of known systems and methods, would appreciate the use of
the invention for its intended purposes and benefits in any number
of alternative embodiments.
Embodiments of the invention described herein comprise a canister
vacuum. However, the invention is not limited to a canister vacuum,
but rather, a person having ordinary skill in the art would
recognize that the invention can also be applied to upright vacuums
or other apparatus requiring particle separation from an
airflow.
Three embodiments of the invention will now be described by
reference to the accompanying schematic drawings on which FIGS. 1-4
shows the first embodiment of the invention, FIGS. 5 and 6 shows
the second embodiment and FIGS. 7 and 8 show the third embodiment
whereas FIG. 9 is a schematic drawing of a suitable filter rotating
mechanism.
The vacuum cleaner shown in FIG. 1 has a first filter in an active
position whereas a second filter is in an inactive position during
an ordinary cleaning operation. FIG. 2 shows the same view as FIG.
1 but with the first filter in an inactive position and the second
filter in an active position. FIG. 3 shows the airflow through the
vacuum cleaner when the first filter is cleaned whereas FIG. 4
shows the airflow when the second filter is cleaned. According to
the second embodiment FIG. 5 shows a first filter in an active
position during an ordinary vacuum cleaning operation at the same
time as a second filter is in an inactive stored position whereas
FIG. 6 shows a filter being cleaned in the stored position. FIG. 7
is a schematic view of the third embodiment of the filter cleaning
system whereas FIG. 8 is an exploded view of a vacuum cleaner that
is provided with the last mentioned filter cleaning system.
FIG. 1 schematically shows a vacuum cleaner body 10 that encloses a
single vacuum source such as fan unit 11 and a dust separation unit
12. The dust separation unit 12 is of the so called cyclone type
and comprises a circular chamber 13 that is provided with a
tangential inlet 14 for dust laden air and a central outlet 15 for
clean air. Due to the airflow a vortex is created within the
chamber 13 and the dust particles are separated from the airflow by
means of the centrifugal forces and are thrown into a dust
collecting container 16 via an opening 17.
The inlet 14 is via a channel 18 connected to an opening 19 in the
vacuum cleaner body that in a conventional way can be connected to
a vacuum cleaner nozzle 20 via a hose 21 and a tube shaft 22. The
central cyclone outlet 15 is connected to a channel 23 via a valve
24 such that the airflow can be directed to a first or a second
section 23a, 23b of the channel 23. The sections 23a and 23b are
via valves 25 and 26 connected to a common channel 27 that by means
of a further valve 28 is branched off from the channel 18.
Channel section 23a ends in a the central parts of a first tube
shaped filter cartridge 29 that is provided with a grip 30 that is
accessible from the outside of the vacuum cleaner. The cartridge 29
is inserted in a first filter space 31, shaped as a filter holder,
provided at the vacuum cleaner body and can easily be removed from
the space. The filter cartridge 29 is preferably made from a
material that can be cleaned manually or by a washing
operation.
Channel section 23b in a corresponding way ends in the central part
of a second tube shaped filter cartridge 32 provided with a grip 33
accessible from the outside of the vacuum cleaner. This cartridge
is inserted in a second filter space 34 and has the same design and
filter material as the first mentioned cartridge 29.
The first as well as the second filter space 31, 34 offers a free
space around each filter cartridge which are connected to a common
channel 35 communicating with the fan unit 11. The channel
comprises a first and a second section 35a and 35b each being
provided with a valve 36 and 37 that can connect the section with
the ambient air.
The arrangement operates in the following manner. During an
ordinary cleaning operation, see FIG. 1, the valve 28 is in such a
position that the opening to the branched off channel 27 is closed.
Dust laden air is taken in through the nozzle 20 and is distributed
through the tube shaft 22, the hose 21 and the channel 18 to the
cyclone chamber 13. The major part of the dust particles are
separated in the cyclone chamber 13 and are distributed to the
collecting container 16. The clean air with a minor part of smaller
particles flows out through the outlet 15 at the centre of the
cyclone chamber 13 and is by means of the valve 24 directed into
the second section 23b and is by the valve 26 directed further into
the central part of the second tubular filter cartridge 32. The air
then flows through the filter material in the cartridge, in which
the major part of the remaining particles are filtered out, before
the air reaches the filter space outside the filter cartridge 32
from which the air flows further into the second section 35b of the
channel 35 before entering into the fan unit 11. The air then
escapes from the vacuum cleaner out to the ambient possibly via an
exhaust filter (not shown) that might be of the Hepafilter type.
During this procedure the valves 36 and 37 are in such positions
that they keep the openings to the ambient air closed.
Assuming that the second filter cartridge 32 gets clogged the
operator has the possibility to continue the vacuum cleaning
operation, see FIG. 2, simply by changing the airflow direction
from the second filter cartridge 32 to the first filter cartridge
29. This is effected by changing the positions of the valve 24 such
that the clean air flows from the cyclone outlet 15 through the
first section 23a of the channel 23 via the valve 25 into the
central part of the filter cartridge 29 from which the air flows
through the filter material and into the first section 35a of the
channel before reaching the fan unit 11.
The operator also has the possibility to clean each filter
cartridge in a simple manner by switching the airflow direction in
the arrangement. FIG. 3 shows how the second filter cartridge 32 is
cleaned. Ambient air is allowed to enter into the system by means
of the valve 37. This air flows through a part of the channel
section 35b into the filter space 34 outside the filter cartridge
32 and further through the filter material to the central part of
the cartridge. Particles that have been clogged at the inside of
the filter cartridge 32 are torn away and are taken up by the
airflow and are by means of the valves 26 and 28 distributed
through the branched off channel 27 and a part of the channel 18
into the cyclone chamber 13. In order to get sufficient cleaning of
the filter there preferably are means, not shown, for concentrating
the airflow through the filter to a smaller part of the total
filter area such that the air velocity increases through this part.
By gradually moving the airflow with respect to the filter surface,
for instance by rotating the filter manually or automatically, the
complete filter area will be cleaned. From the clean air outlet 15
of the chamber 13 the air then flows through the first section 23a
of the channel 23 into the interior of the first filter cartridge
29 and through the filter material before leaving the first filter
space 31 via the first section 35a of the channel 35 to the fan
unit 11. During this cleaning procedure the valve 25 keeps the
opening between the first section 23a and the branched off channel
27 closed and the valve 36 keeps the opening between the first
section 35a and the ambient air closed.
FIG. 4 shows how the first filter cartridge 29 is cleaned in a
corresponding way. The operator activates the various valves such
that ambient air is now allowed to enter into the system by means
of the valve 36. The air flows, in a similar way that has been
described above, through the first filter cartridge 29 and the
branched off channel 27 into a part of the channel 18 and further
into the cyclone chamber 13. The clean airflow from the outlet 15
in the cyclone chamber 13 is then directed through the second
section 23b of the channel 23 before entering into the interior of
the second filter cartridge 32 where the major part of the
remaining particles are separated. After flowing through the filter
material the air is directed through the second section 35b of the
channel 35 and further into the fan unit 11.
Thus, the arrangement described above makes it possible to continue
a cleaning operation even if the efficiency decreases due to
clogging in the filter by simply directing the airflow from the
cyclone to another filter. The arrangement also makes it possible
to clean the filters without taking them out of the vacuum cleaner
simply by activating or deactivating the different valves such that
the airflow is shifted in a suitable way. Since the filter
cartridges are easy to remove from the vacuum cleaner body it is
also easy for the operator to take away the cartridge and clean it
more thoroughly in a washing operation if the cartridges are not
fully cleaned in the suction operation described above.
The embodiment shown in FIGS. 5-6 comprises a single vacuum source
such as a fan unit 41 and a dust separation unit 42 of the cyclone
type having a circular chamber 43 with an inlet 44 for dust laden
air and an outlet 45 for partially cleaned air. The separation unit
is connected with a dust collecting container 46 via an opening 47
through which the dust particles are distributed into the
container. The inlet 44 is in the same manner as described above
via a channel 48 connected to a vacuum cleaner nozzle 49. The air
outlet 45 of the cyclone is connected to a channel 50 that directs
the cleaned air to a first filter space 51 for a first tube shaped
filter cartridge 52 that is removably inserted into said space. A
central part 53 of the cartridge 52 communicates via a channel 54
with the fan unit 41 such that air is sucked from the central part
53 to the fan and then is directed to the ambient air.
The channel 48 is provided with a valve 55 that allows air to be
taken in to the chamber through a branched off channel 56 at the
same time as the airflow from the nozzle 49 is prevented from
flowing to the inlet 44. The channel 56 is connected to a second
filter space 57 of a second removable, tube shaped filter cartridge
58. The central part 59 of the cartridge 58 is connected to a tube
60 provided with an opening 61 through which air can be sucked into
the filter cartridge.
The system according to FIGS. 5 and 6 operate in the following
manner. During normal vacuum cleaning work (see FIG. 5) dust laden
air is sucked into the chamber 43 through the nozzle 49 and the
channel 48. During this procedure the valve is in such a position
that the connection to the channel 56 is closed. Consequently dirt
particles are separated in the chamber 43 and are directed into the
dust collecting container 46. The air which now has been partially
cleaned is sucked through the outlet 45 and the channel 50 to the
filter space 51 from which the air flows through the filter
material of the cartridge 52 into the central part 53 of the
cartridge. This means that the major part of the particles that
have not been separated in the chamber 43 is deposited on the
filter material when the air flows through the filter material and
further into the channel 54 from which it leaves to the ambient air
via the fan unit 41.
When the first cartridge 52 becomes clogged and provided that the
second cartridge 58 has been cleaned the operator switches off the
vacuum cleaner and exchanges the position of the two cartridges
(see FIG. 6) such that it is possible to continue the work but this
time with the clean cartridge 58 in the space 51 and the dirty
cartridge 52 in the space 57.
If the operator finds it suitable to clean the cartridge 52 which
is now in the filter space 57 he activates the valve 55 such that
the connection between the channel 56 and the inlet opening 44 is
opened at the same time as the connection to the nozzle 49 is
closed. This means that ambient air is drawn through the opening 60
into the central part of the cartridge 52 and further through the
filter material into the filter space 57. This means that the dust
particles on the filter surfaces become free and are transported
via the channel 48 to the chamber 43 together with the airflow. The
major part of the dust particles are, as mentioned before,
separated in the chamber 43 and collected in the container 46
whereas the clean air leaving through the outlet 45 enters the
filter space 51 for the cartridge 58 where the air is filtered
through the filter material before leaving the vacuum cleaner
through the channel 54 and the fan unit 41. It should in this
connection be mentioned that in order to get an efficient filter
cleaning of the filter cartridge the airflow is concentrated to a
small area of the filter surface when the air flows from the inner
to the outer side of the filter cartridge.
According to a further embodiment of the invention it is also
possible to use the invention in a conventional cyclone vacuum
cleaner that is provided with solely one active filter that is
easily removable and that is placed in a filter space connected to
the air cyclone and the fan unit. Such a vacuum cleaner can be
provided with at least one additional non active filter space
serving as a storage place for a passive filter which is easily
accessible from the outside of the vacuum cleaner. When the active
filter has been clogged during a vacuum cleaner operation the
operator can easily remove the active filter from the active filter
space and replace it with a cleaned filter that is taken out from
the additional filter space. The operator can then finish the
cleaning operation and also use the vacuum cleaner for additional
cleaning operations before removing the clogged filter and wash or
clean it manually. When the filter has been cleaned it is again
inserted into the additional non active filter space in order to be
used when the active filter has been clogged.
The vacuum cleaner according to FIG. 7 and FIG. 8 comprises an
inlet opening 110 for dust laden air that in a conventional manner
can be connected to a vacuum cleaner nozzle (not shown) via a hose
111. The inlet opening continues as an inlet channel 112 that ends
in a mainly cylindrical cyclone chamber 113. The cyclone chamber
113 communicates via an opening 114 with a dust collecting
container 115 and has a tube shaped outlet 116 arranged in the
central part of the cyclone chamber. This outlet 116 communicates
with an air passage 117 ending in a filter chamber 118 in which a
first filter cartridge 119 is inserted. The filter cartridge
preferably is provided with one or several folded filter layers
arranged around a central channel 120 and having its outer
periphery placed at some distance from the inner wall of the filter
chamber 118. The upper portion of the filter cartridge is turnably
and removably arranged at one end of a support structure 121 shaped
as a handle.
The support structure 121 is provided with a turnable knob 122 that
is connected to the filter cartridge 119 such that the filter
cartridge follows the rotating motion of the knob 122 if it is
turned manually. The rotating motion of the knob or the filter
cartridge might of course also be achieved automatically by an
electric motor or some other means. The central channel 120 of the
filter cartridge is at its lower part in communication with an air
channel 123 connected to the air inlet of a vacuum source such as a
motor/fan unit 124 whose outlet communicates with the ambient
air.
The vacuum cleaner is also provided with a filter cleaning chamber
125 in which a second filter cartridge 126, preferably of the same
type as the first filter cartridge, is inserted. The second filter
cartridge 126 is in the same manner as the first filter cartridge
119 removably arranged at the other end of the support structure
121 and is also rotatably connected to a knob 127 secured to the
support structure 121. The second filter cartridge has a central
channel 128 that is connected to an air inlet 129 arranged at the
bottom of the filter cleaning chamber 125 and tha communicates with
the ambient air. The filter cleaner chamber is further provided
with an outlet 130 that is shaped as an elongated narrow opening
extending mainly parallel to the axis of the filter cartridge close
to the outer periphery of the cartridge. The outlet 130 is via an
air passage 131 and a valve 132 connected to the inlet channel 112
for dust laden air.
The vacuum cleaner is provided with an electric circuit that is
connected to a pressure sensor 133 for sensing the pressure drop
over the first filter cartridge 119 in order to indicate when the
filter has been clogged. When this occurs a bulb or an acoustic
signal is activated. There also is a sensor 134 arranged close to,
or within, the filter cleaning chamber 125 for achieving a signal
to the electric circuit when the filter in the filter cleaning
chamber has been cleaned. This sensor is connected to a sensor
system that includes a permanent magnet 135 arranged on the
periphery of each knob 122, 127 and is connected such that the
vacuum cleaner motor starts when the knob 122 is being turned and
shuts off when a predetermined complete turns have been made by the
operator.
The device operates and is used in the following manner. When the
operator starts the vacuum cleaner dust laden air is sucked in
through the hose111 and the inlet channel 112 to the cyclone
chamber 113. Since the inlet flow is arranged to be tangentially to
the mainly cylindrical cyclone chamber 113 a vortex is created and
the particles are, due to centrifugal forces, thrown towards the
periphery and out through the opening 114 into the dust container
where they are collected. The cleaned airflows through the outlet
116 of the cyclone chamber 113 into the air passage 117 and
continues into the filter chamber 118 before the air reaches the
first filter cartridge 119. Smaller particles that have passed the
cyclone chamber are now separated in the filter material and the
air then via the central channel 120 flows to the motor/fan unit
124 and is distributed to the ambient air.
When the first filter cartridge has been clogged this is indicated
by the light bulb or the acoustic signal via the pressure sensor
133. The operator can now switch off the vacuum cleaner and open a
cover at the front part of the vacuum cleaner that is connected to
the valve 132 such that the valve closes the outer part of the
inlet channel 112 and opens up the connection between the inner
part of this channel and the air passage 131. The operator then
lifts the support structure 121 to which the first and second
cartridge 119, 126 are secured and turns it 180.degree. about a
mainly vertical axis before putting the first filter cartridge 119
into the filter cleaning chamber 125 at the same time as the second
filter cartridge 126 is inserted in the filter chamber 118.
The operator then manually turns the knob 122 thereby starting to
rotate the filter cartridge 119 such that the permanent magnet 135
influences the sensor 134 and creates a signal starting the
motor/fan unit 124. This means that fresh air is now sucked in from
the ambient air through the air inlet 129 and into the central
channel 120 of the cartridge 119. The air then flows through the
part of the filter material facing the narrow outlet 130 with great
velocity thereby releasing the dust particles that have been taken
up previously and carrying them via the passage 131 and the inner
part of the inlet channel 112 to the cyclone chamber 113. The major
part of the particles are separated and collected in the dust
container 115 whereas the cleaned air leaves through the outlet 116
and flows to the filter chamber 118 via the air passage 117.
The air is then sucked through the filter material and remaining
particles are taken up by the second filter cartridge 126 before
the air leaves to atmosphere via the air channel 123 and the
motor/fan unit 124. When the operator has finished a predetermined
number of complete turns of the knob 122 the motor/fan unit is
stopped indicating that the filter has been cleaned. The operator
now closes the cover which means that the valve 132 is moved back
to its original position and the operator can again start the
vacuum cleaner and continue his work. When the second filter
cartridge 126 has been clogged the procedure described above will
be repeated thereby switching the two filter cartridges 119, 126
back to their original positions.
As has been mentioned above the rotating motion of the filter
cartridge might as well be realized by mechanical and/or electrical
means and for instance be arranged such that the fan and the
rotation starts automatically when the dirty filter has been
inserted into the filter cleaning chamber.
A plan view of a preferable filter rotating mechanism is shown in
FIG. 9 Such a mechanism is arranged at each end of an elongated
filter support structure 210 for two cylindrical filters (only one
half is shown). Each end of the filter support structure comprises
a mainly circular bottom plate 211 with an upwardly extending
flange 212 on which a rotatable cup shaped cover 213 is arranged.
The cover is provided with an annular element 214 having a number
of several outwardly extending fins 215. During rotation of the
cover 213 the fins will come into engagement with a slider 216 that
is linearly movable in an opening 217 in the flange 212. The part
of the slider 216 that is below the cover is provided with two
resilient tongues 218 that rest against the flange 212 and
consequently push the slider towards the rotation axis A of the
cover 213. The part of the slider that is placed outside the
opening 217 is arranged such that it can act against a micro switch
219 connected to the electrical system of the vacuum cleaner. A
filter cartridge 220 is placed below the bottom plate 211 and is
removably secured to the cover 213 such that it follows the
rotation of the cover. The filter cartridge is mainly cylindrical
and has a folded outer surface with the folding lines parallel to
said axis A.
The rotating mechanism operates in the following manner. When a
filter has been used and it is time to shift the clogged filter
from the filter chamber to the cleaning chamber the support
structure with the two filters are turned 180.degree. and the
filters are then inserted in their new positions. The operator
starts to turn the cover 213 which means that the slider 216 is
moved back and forth by the fins 215 and acts on the switch 219
thereby establishing electrical pulses that can be counted by the
electric equipment within the vacuum cleaner. After a few pulses
the fan is arranged to start. Simultaneously the folds of the
filter are successively passing the elongated, narrow, outlet
opening in the cleaning chamber such that air can be drawn from the
inlet opening in the cleaning chamber through the lower central
inlet opening of the filter cartridge, through the filter material
and into said outlet opening. After a predetermined number of
complete turns and the corresponding amount of pulses the motor of
the fan is fan is shut off by the electric system.
In order to make the dust removal even more efficient it is
possible to provide the walls of the cleaning chamber with ridges
or similar elements such that dust is wiped off the folds when
passing the ridges during the rotation of the filter.
* * * * *